% /*******************************************************************************
%  * Rounding(Up/Down) toward zero
%  * *****************************************************************************
%  * Depending on its sign negative/positive, it's rounded up/down (toward zero).  
%  * @param x     Input number in (-1,1)
%  * @param bits  Significant bits(or #bits to keep)
%  * @return      Rounded number
%  */
function x_round = rnd_zero(x,bits)
if (x < 0)
    x_round = rnd_up(x, bits);
else
    x_round = rnd_down(x, bits);
end
end